It is estimated that 220 million women around the world do not have access to contraceptives or information on them.
In some countries women need written consent from their husbands before they can talk to a doctor about contraception while in others, family planning services are not offered to adolescents or unmarried women.
In developing countries, contraceptives are frequently out of stock when women try to get them.
Delegates at the summit are hoping to get 120 million women better access to contraceptives, information and services by 2020.
More top news
Billionaire Microsoft co-founder Paul Allen has claimed discovery of the Japanese battleship Musashi that was sunk by the US Navy in 1945.
Friday will be mostly dry with sunny spells for much of the UK. Temperatures will be mild across the country.
Some famous Liberal Democrat names will be fighting for their political lives in the election, now just over two months away.